Sheetrock interior walls visible from crawl space?

Anyone have an issue with this? A tall section of the crawl space (split-level home) had just sheetrock walls (insulated) separating the living space from the crawl space. I’ve seen it once or twice before, but now I’m starting to question it.

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I have only seen it once, I would also like to see better protection. like OSB or cement board . but i do know if it is called for. good post Joe

It is common in my area.

…same here, especially on tri and quad levels.

Are these air conditioned homes?
Are the crawl spaces quite dry?

Because it is inside of the building envelope it is permitted, but it appears from photo #1 that fire blocking could be missing where the horiziontal floor intersects the vertical wall.(Fireblocking shall be installed to cut off all concealed draft openings)


That’s no different then exposed insulation in an attic.

Central HVAC. The crawl was dry, but there was high moisture in the wood due to high humidity in the air. Not much of a vapor barrier. Typical stinky, musty crawl space.

I didn’t say anything about it.

However, an attic is dry. Not musty. I just worried about the increased potential for musty odors and possible long term deterioration of the sheetrock.


If moisture is your concern does the crawlspace have enough ventilation?

If the interior of the house is air conditioned and moist air/moisture in the crawl space can reach the back of the cool drywall through gaps in the installed insulation or by air movement through the batts, moisture may condense on the back of the drywall possibly leading to mould growth.

Although not required by the SOP, I would’ve removed a piece or 2 of the insulation looking for any signs of suspected mould growth on the back of the drywall. Joe Lstiburek has some videos of mould on the back of vinyl wallpaper applied to the inner side of air conditioned drywall.

This one did not in that particular area. It was a dead zone for air movement. Adjacent to a garage and the next unit of a townhome. I called out the high moisture content in the wood. Lots of condensation going on. Damp soil due to condensation.

I think next time I will take Brian’s advice and peek behind the insulation. Since I could see the sheetrock, I know gaps exist that would allow air to get between the insulation and sheetrock.

Okay, now we get more of the story…

Is this wall for the garage or next unit over? If yes to either, needs to be firewall rated.

If not, than it’s not much different than basements and their staircases (my area).

Garage and next unit were protected by rated firewall (brick).